1. Field of the Invention
The subject invention relates generally to a motion transmitting remote control assembly of the type for transmitting forces along a curved path by a flexible core element supported in a conduit and, more specifically, to an improved adjustment for adjusting the length of either the core element or the conduit.
2. Description of the Prior Art
Motion transmitting remote control assemblies of the type for transmitting motion in a curved path by means of a flexible motion transmitting core element are frequently used in automotive applications to control the movement of a device from a remote location. For example, the air intake valve of an internal combustion engine is typically controlled from either a foot pedal or hand lever. Other examples include the remote manipulation of transmissions, ventilation systems, fuel doors, and hood releases via a motion transmitting remote control assembly. Such motion transmitting remote control assemblies may comprise a protective sheath-like conduit which slidably supports an internal moving core element. The conduits are often of the composite type having an inner tubular liner defining the internal boundaries of a core passage, at least one metallic supportive lay wire wrapped helically about the liner, and an outer cover disposed about the lay wire. Alternatively, the conduit may be of the more traditional Bowden type construction. The core element may be either a single wire or a multi-stranded cable.
Because of the inevitable dimensional variations occurring in any complex manufactured assembly, it is necessary to incorporate a length adjustment feature into the remote control assembly. That is, the length adjustment feature is provided to prevent slack or over-tension in the remote control assembly, and also to ease the assembly process. For applications requiring relatively high longitudinal force transfer, such as when remotely controlling an automatic transmission, the prior art teaches a series of transversely extending teeth on one surface of a rectangular housing and a slider internally of the housing with an interlock member having teeth of its own transversely slidable to engage the housing to effectively lock the slider in a fixed position relative to the housing.
One example of such a prior art remote control assembly may be found in U.S. Pat. No. 5,709,132, issued to Irish et al. on Jan. 20, 1998; and assigned to the assignee of the subject invention. As shown in U.S. Pat. No. 5,709,132, the assembly includes a slider fixed with respect to a length adjuster with an interlock. Interlock includes a plurality of teeth which interconnect with the teeth disposed along the top surface of length adjuster. The amount of longitudinal strip force which the assembly can withstand is directly proportional to the number of interlock teeth which interconnect with length adjuster teeth. Therefore, additional interlock teeth are required to increase the amount of longitudinal strip force which the assembly can withstand. However, increasing the number of interlock teeth lengthens the interlock thereby decreasing the overall length to travel ratio or, in other words, the amount of length adjustment available. Accordingly, there is a need for a remote control assembly capable of withstanding higher longitudinal strip forces without reducing its overall length to travel ratio.